SURVIVE TO FISH ANOTHER DAY

ACKNOWLEDGMENTS
The completion of this "Best Practices Guide to Vessel Stability" would not have been possible without the assistance and input of numerous people and organizations. Thanks go to Mr. John Womack, Naval Architect, and Dr. Bruce Johnson, Professor Emeritus US Naval Academy, for their partial-authorship of this book, to LT Eric Cooper (US. Coast Guard) for his revisions, the Commercial Fishing Industry Vessel Safety Advisory Committee (CFIVSAC) Subcommittee on Stability for their input and peer review, Transport Canada for providing examples of previous successful booklets, and the US. Coast Guard's Naval Architecture Division for their technical support and review. Special thanks go to US. Coast Guard’s Office of Compliance for the countless hours spent formatting pages, editing content, and recreating artwork. Without these efforts, this booklet would never have been completed. Thank you to all who contributed.
4

Table of Contents
Section Page
Acknowledgements
4
Introduction
6
What is Stability
7 When is a Vessel Stable or Unstable
9 Key Terms Used in Fishing Vessel Stability
10 How Stability Works
11 How is a Fishing Vessel’s Stability Displayed
16 Initial vs. Overall Stability - The Hidden Danger
24 Free Surface - Shifting into Danger
29 Fishing Operations - Danger at the Helm
36 Wind and Waves - Danger in Heavy Seas
42 Prudent Seamanship - Keeping a Level Vessel
50
Damage Control
53 List of Stability Terms
61 List of Contacts for Additional Information
63 5

Introduction
This booklet introduces the basic concepts of a fishing vessel’s stability to fishing vessel crews, vessel owners, and other interested parties in the commercial fishing community. The primary stability concepts explored are
• What is stability
• How does stability work
• How do Naval Architects determine a fishing vessel’s stability to develop safe operating guidance
• What is the difference between initial and overall stability
• What is the hidden danger in using a fishing vessel’s feel, which is its initial stability, to gauge if there is adequate overall stability
• What are the effects of common fishing vessel operations on its stability
• What can fishing vessel crews do to maintain adequate stability This booklet treats a wide range of subjects concerning fishing vessel stability. To assist the reader, critical important lessons are listed at the beginning of each section. Please consider each topic separately, remembering the following five important take-home messages.
1. A fishing vessel’s stability is created by the interaction between the weight of the vessel pushing down and the buoyancy of the hull pushing up.
2. The feel of a vessel indicates how much initial stability it has - it does not indicate if the vessel has enough overall stability fora safe voyage.
3. A fishing vessel’s stability is constantly changing throughout its voyage.
4. How a fishing vessel is loaded and operated affects the stability levels positively or negatively.
5. Work with your naval architect to determine suitable stability guidance your vessel’s unique stability characteristics.
6

Download 7.25 Mb.

Share with your friends: